Abstract: Disclosed is a novel transition metal composition of a metallacycle structure represented by the formula ##STR1## wherein M.sup.1 is an element of Group IVB in the Periodic Table, M.sup.2 is an element of Group IIIA in the Periodic Table, R.sup.1 and R.sup.2 each are for instance a cyclopentadienyl group, R.sup.3 and R.sup.4 each are for instance a hydrocarbon group, R5 and R6 each are a hydrogen atom and R7 and R8 indicate an indan ring formed by bonding to each other.

Abstract: A catalyst comprises a composition resulting from mutual contact of the following Components. (A), (B), (C) and (D):said Component (A) being a reaction product resulting from mutual contact of components (a), (b) and (c);said component (a) being represented by the formulaMe.sup.1 R.sup.1.sub.p (OR.sup.2).sub.q X.sup.1.sub.4-p-q Iwherein R.sup.1 and R.sup.2 each are a C.sub.1 -C.sub.24 hydrocarbon moieties, X.sup.1 is a hydrogen atom or a halogen atom, Me.sup.1 is titanium, zirconium or hafnium, p and q are 0.ltoreq.p.ltoreq.4, 0.ltoreq.q.ltoreq.4 and 0.ltoreq.p+q.ltoreq.4,said component (b) being represented by the formulaMe.sup.2 R.sup.3.sub.m (OR.sup.4).sub.n X.sup.2.sub.z-m-n IIwherein R.sup.3 and R.sup.4 each are a C.sub.1 -C.sub.2 4 hydrocarbon moieties, X.sup.2 is a hydrogen atom or a halogen atom, Me.sup.2 is an element of Groups I to III in the Periodic Table, z is a valence of Me.sup.2, and m and n are 0.ltoreq.m.ltoreq.z, 0.ltoreq.n.ltoreq.z and 0.ltoreq.m+n.ltoreq.

Abstract: According to the present invention, there are provided a catalyst and a process for the preparation of polyolefins having a relatively wide molecular weight distribution, good particle properties, a narrow composition distribution in copolymerization and a high molecular weight and being less sticky. The catalyst is prepared by contacting the following constituents (1) to (4) with one another:(1) a compound represented by the general formula Me.sup.1 R.sup.1.sub.p (OR.sup.2).sub.q X.sub.4-p-q, where Me.sup.1 is Zr, Ti or Hf, R.sup.1 and R.sup.2 are each independently a hydrocarbon group having 1 to 24 carbon atoms, X is a halogen atom, p and q are each an integer in the ranges of 0.ltoreq.p.ltoreq.4 and 0.ltoreq.q.ltoreq.4 , provided 0.ltoreq.p+q.ltoreq.4;(2) a compound represented by the general formula Me.sup.2 R.sup.3.sub.m (OR.sup.4).sub.n X.sup.2.sub.z-m-n, where Me.sup.2 is a Group I-III element in the Periodic Table, R.sup.3 and R.sup.

Abstract: An olefin polymerization is conducted in the presence of a catalyst comprising a solid catalyst component and an organometallic compound, said solid catalyst component being prepared by reacting the following components [I], [II] and [III] with one another:[I] a reaction product obtained by reacting the following components (1), (2) and (3) with one another:(1) a silicon oxide and/or an aluminum oxide;(2) a reaction product obtained by the reaction of a magnesium halide and a compound represented by the general formula Me(OR).sub.n X.sub.z-n where Me represents an element of Groups I to IV in the Periodic Table, z represents the valence of the element Me, n is 0<n.ltoreq.z, X is a halogen atom and R is a hydrocarbon group having 1 to 20 carbon atoms; and(3) a titanium compound represented by the general formula Ti(OR.sup.1).sub.m X.sub.4-m ; where R.sup.1 is a hydrocarbon group having 1 to 20 carbon atoms, X is a halogen atom and m is 0.ltoreq.m.ltoreq.

Abstract: The present invention provides a movable magnetic head unit including a signal transmission element. The transmission element transmits by wireless, i.e., through noncontact transmission, a control signal for driving an electromechanical transducing element fixed to a rotary magnetic head. Therefore, noises are prevented from appearing on a display, and stable compensation in the deviation of the magnetic head and a high reliability of the magnetic head unit can be attained.

Abstract: A process for the production of polyolefins is provided which comprises polymerizing or copolymerizing olefins in the presence of a catalyst composition which includes a catalyst component (I) resulting from mutual contact of sub-components (A) and (B), and a catalyst component (II). Sub-component (A) is of the formulaR.sup.1.sub.p Me.sup.1 X.sup.1.sub.4-p and/or R.sup.1.sub.2 Me.sup.1 X.sup.1'and sub-component (B) is a modified organoaluminum compound having Al--O--Al bonds. Catalyst component (II) is an admixture of sub-component (C), which is a transition metal elemental compound of Groups VII-VIII, and one or more of triethylaluminum, triisobutylaluminum, diethyl zinc, n-butyllithium, and butylmagnesiumchloride. The catalyst components (I) and/or (II) are contacted with a carrier during or after the preparation of the components (I) and/or (II).

Abstract: Polyolefins exhibiting better particle properties are prepared by polymerizing an olefin or olefins in the presence of a catalyst comprising a solid catalyst component being prepared by the reaction of the following components ?I! and ?II!:?I! a reaction product obtained by reacting the following components (1), (2) and (3) with one another:(1) a silicon oxide and/or an aluminum oxide;(2) a reaction product obtained by the reaction of a magnesium halide and compound represented by the general formula Me(OR).sub.n X.sub.z-n wherein Me represents an element of Groups I to IV in the Periodic Table, z represents the valence of the element Me, n is 0<n.ltoreq.z, X is a halogen atom, and R is a hydrocarbon radical having 1 to 20 carbon atoms; and(3) a titanium compound represented by the general formula Ti(OR).sub.n X.sub.4-n wherein R is a hydrocarbon radical having 1 to 20 carbon atoms, X is a halogen atom, and n is 0.ltoreq.n.ltoreq.

Abstract: A novel olefin polymerization catalyst is obtained by contacting the following components (1) to (5) with one another: (1) a compound represented by the general formula Me.sup.1 R.sup.1.sub.p (OR.sup.2).sub.q X.sup.1.sub.4-p-q, (2) a compound represented by the general formula Me.sup.2 R.sup.3.sub.m (OR.sup.4).sub.n X.sup.2.sub.z-m-n, (3) an organocyclic compound having conjugated double bonds; (4) a modified organoaluminum compound having Al--O--Al bond(s); and (5) a silicon oxide and/or an aluminum oxide both having characteristic average particle diameter, specific surface area, volume of pores ranging in pore radius from 18 to 1,000 Angstroms, apparent specific gravity not lower than 0.32, and proportion of 50 .mu.m or smaller particles.

Abstract: A catalyst comprises a composition resulting from mutual contact of the following Components (A), (B), (C) and (D):said Component (A) being a reaction product resulting from mutual contact of components (a), (b) and (c);said component (a) being represented by the formulaMe.sup.1 R.sup.1.sub.p (OR.sup.2).sub.q X.sup.1.sub.4-p-q Iwherein R.sup.1 and R.sup.2 each are a C.sub.1 -C.sub.24 hydrocarbon moieties, X.sup.1 is a hydrogen atom or a halogen atom, Me.sup.1 is titanium, zirconium or hafnium, p and q are 0.ltoreq.p.ltoreq.4, 0.ltoreq.q.ltoreq.4 and 0.ltoreq.p+q.ltoreq.4,said component (b) being represented by the formulaMe.sup.2 R.sup.3.sub.m(OR.sup.4).sub.n X.sup.2.sub.z-m-n IIwherein R.sup.3 and R.sup.4 each are a C.sub.1 -C.sub.24 hydrocarbon moieties, X.sup.2 is a hydrogen atom or a halogen atom, Me.sup.2 is an element of Groups I to III in the Periodic Table, z is a valence of Me.sup.2, and m and n are 0.ltoreq.m.ltoreq.z, 0.ltoreq.n.ltoreq.z and 0<m+n.ltoreq.

Abstract: The present invention provides a movable magnetic head unit including a signal transmission element. The movable magnetic head is mounted upon a rotary drum of a drum assembly which also includes a stationary drum, the rotary and stationary drums being supported by a shaft. The signal transmission element transmits a control signal wirelessly to the rotary drum to drive an electromechanical transducing element which moves the magnetic head. The signal transmission element may include rotary transformers, mounted on the rotary and stationary drums, facing each other. In a further embodiment, the signal transmission element may include an optical transmitter for optically transmitting the position control signal to an optical receiver mounted on the rotary drum. Wireless transmission of the position control signal prevents noises from appearing on a display, enables stable compensation of deviations of the magnetic head and improves reliability of the magnetic head unit.

Abstract: Olefin is polymerized using a catalyst comprising a solid catalyst component and an organometallic compound, the solid catalyst component being prepared by reacting 1 a reaction product obtained by reacting the reaction product of Si oxide and/or Al oxide and Ti compound or both Ti compound and V compound (Ti.V component) with organic Al compound, with 2 a reaction product obtained by the reaction of Mg halide, a compound of the general formula Me(OR).sub.n X.sub.z-n and Ti.V component (optional component), and further reacting the reaction product of the above 1 and 2 with 3 a compound of the general formula R.sub.p Si(OR).sub.q X.sub.4-p-q.

Abstract: An effective catalyst carrier for use in the polymerization of olefins is provided.Said carrier comprises particles of silicon oxide or aluminum oxide satisfying the following characteristics (A) to (E):(A) An average particle diameter as measured by the sieving method is in the range of 20 to 150 .mu.m.(B) A specific surface area as measured by the BET method is in the range of 150 to 600 m.sup.2 /g.(C) The volume of pores ranging in pore radius from 18 to 1,000 Angstroms as measured by the mercury penetration method is in the range of 0.3 to 2.0 cm.sup.3 /g.(D) An apparent specific gravity as measured according to JIS K6220-6.8 is not lower than 0.32.(E) After the particles classified in the range of between 53 .mu.m and 75 .mu.m by the sieving method have been subjected to an ultrasonic disintegration treatment at 40 KHz, 35 W, for 20 minutes, the proportion of 50 .mu.m or smaller particles, i.e., degree of ultrasonic disintegration, is not more than 30%.

Abstract: A resin composition comprises 100 parts by weight of an ethylene-base resin comprising at least 2 wt. % of linear low-density polyethylene and 0.1-30 parts by weight of an organopolysiloxane having an average molecular weight of at least 100,000. The resin composition can be produced by melting and kneading the organopolysiloxane together with the linear low-density polyethylene and then melting and kneading the resulting polymer blend together with the ethylene-base resin other than the linear low-density polyethylene. The resin composition may additionally comprise 0.1-100 parts by weight of a propylene-base resin. In the latter resin composition, the organopolysiloxane is contained in an amount of 0.1-30 parts by weight per 100 parts by weight of the sum of the ethylene-base resin and the propylene-base resin.

Abstract: In the preparation of polyolefin in a vapor phase polymerization using catalysts comprising a solid catalyst component containing titanium and/or vanadium; and magnesium and an organoaluminum compound, when the reaction is stopped for a certain period of time, the restarting of reaction is possible by feeding in the first place an organoaluminum compound into the reaction system with retaining of polymer particles in the reactor.

Abstract: A polyolefin having superior particle properties such as an extremely high bulk density, a large average particle diameter and a narrow particle size distribution, and having a narrow molecular weight distribution, is obtained in high yield, by polymerizing an olefin, using a catalyst comprising a solid catalyst component and an organometallic compound, the solid catalyst component being obtained by reacting a) a silicon oxide and/or an aluminum oxide, the reaction product of an organomagnesium compound and a compound of the general formula Me(OR).sub.n X.sub.Z-n, and a titanium compound, in the presence of ROH, and further reacting the resulting reaction product with a compound of the general formula AlR.sub.q X.sub.3-q.

Abstract: Polyolefins having better particle properties are obtained by polymerizing olefins in the presence of a catalyst comprising a solid catalyst component and an organometallic compound, the said solid catalyst component being prepared by reacting the following components [I] and [II] and further reacting the resulting reaction product with the following component [III]:[I] a reaction product obtained by reacting:(1) a silicon oxide and/or an aluminum oxide, and(2) a titanium compound, or a titanium compound and a vanadium compound, and further reacting the resulting reaction product with:(3) an organoaluminum compound;[II] a reaction product obtained by the reaction of:(1) a magnesium halide, and(2) a compound represented by the general formula Me(OR).sub.n X.sub.z-n wherein Me represents an element of Groups I to IV in the Periodic Table, z represents the valence of the element Me, n is 0<n.ltoreq.

Abstract: A resin composition comprises 100 parts by weight of an ethylene-base resin comprising at least 2 wt. % of linear low-density polyethylene and 0.1-30 parts by weight of an organopolysiloxane having an average molecular weight of at least 100,000. The resin composition can be produced by melting and kneading the organopolysiloxane together with the linear low-density polyethylene and then melting and kneading the resulting polymer blend together with the ethylene-base resin other than the linear low-density polyethylene. The resin composition may additionally comprise 0.1-100 parts by weight of a propylene-base resin. In the latter resin composition, the organopolysiloxane is contained in an amount of 0.1-30 parts by weight per 100 parts by weight of the sum of the ethylene-base resin and the propylene-base resin.

Abstract: Polyolefins exhibiting better particle properties are prepared by polymerizing an olefin or olefins in the presence of a catalyst comprising a solid catalyst component and an organometallic compound, said solid catalyst component being prepared by the reaction of the following components [I] and [II]:[I] a reaction product obtained by reacting the following components (1), (2) and (3) with one another in the presence of a compound represented by the general formula ROH wherein R is a hydrocarbon radical having 1 to 20 carbon atoms or an organic residue containing such an element as oxygen, nitrogen, sulfur, or chlorine:(1) a silicon oxide and/or an aluminum oxide;(2) a reaction product obtained by the reaction of a magnesium halide and compound represented by the general formula Me(OR).sub.n X.sub.z-n wherein Me represents an element of Groups I to IV in the Periodic Table, z represents the valence of the element Me, n is 0<n.ltoreq.

Abstract: According to the present invention, in a vapor phase polymerization of olefins, there is provided an efficient polyolefin manufacturing process capable of preventing the formation of a sheet-like polymer and allowing an olefin polymerization reaction to be started stably.

Abstract: Polyolefins exhibiting better particle properties are prepared by polymerizing an olefin or olefins in the presence of a catalyst comprising a solid catalyst component and an organometallic compound, the solid catalyst component being prepared by reacting the following components [I] and [II] at first and then reacting the reaction product thus obtained with the following component [III]:[I] a reaction product obtained by reacting:(1) a silicon oxide and/or an aluminum oxide, and(2) a titanium compound, or a titanium compound and a vanadium compound,[II] a reaction product obtained by the reaction of:(1) a magnesium halide,(2) a compound represented by the general formula Me(OR).sub.n X.sub.z-n wherein Me represents an element of J Groups I to IV in the Periodic Table, z represents the valence of the element Me, n is 0<n.ltoreq.